What is the correct spacing between T studded posts?

After you brought the T studded post, please check what is the weight per piece, as usual, it has a light type, regular type, and heavy type.  

According to the wire fence that you used, if the wire fence also light type and you don't need it to be with more strength, the animals will not kick it, then you can put a little longer distance between two post fence.  like, 8feet.

But if you need to control the big animals, then it needs request to the high tensile strength of the fence.  You have to buy heavy-duty wire fence and heavy T post.  The distance between the post also needs to be smaller, like 6 feet, 5feet.

After all, you need to consider the livestock features then you can do some adjustment accordingly.